1. Field of the Invention
The present invention relates to a hair dye composition having excellent dyeing power, being capable of imparting a wide range of colors to the hair without losing their vividness, and showing less color fade over time.
2. Background Art
Hair dyes can be classified by a dye to be used therefor, or by whether they have bleaching action of melanin or not. Typical examples include a two-part permanent hair dye composed of a first part containing an alkali agent, an oxidation dye and optionally a direct dye such as a nitro dye and a second part containing an oxidizing agent; and a one-part semi-permanent hair dye containing an organic acid or an alkali agent, and an acid dye, basic dye or direct dye such as a nitro dye.
The above-described permanent hair dye is however accompanied by the drawback that the color tone imparted by an oxidation dye is not so vivid. Use of a nitro dye or cationic dye for a two-component hair dye containing an oxidizing agent has been attempted in order to produce various color tones (refer to, for example, Japanese Patent Laid-Open Nos. 271435/1994 and 2001-261535). A hair dye added with a nitro dye develops a vivid color just after dyeing, but color fades away remarkably over time and tends to be dull. Use of a cationic dye, on the other hand, involves such problems that it is easily decomposed when mixed with a peroxide serving as an oxidizing agent and it cannot readily be used in combination with an anionic polymer.